CVE-2025-21357 Microsoft Outlook Remote Code Execution Vulnerability
Attackers can execute arbitrary code on systems running Microsoft Outlook via this memory corruption vulnerability.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2025-21357?
CVE-2025-21357 is a medium-severity memory corruption vulnerability in Microsoft 365 Apps, published on 14 Jan 2025. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
Microsoft Outlook Remote Code Execution Vulnerability
Weakness: CWE-908
Which versions are affected by CVE-2025-21357?
It affects 4 products.
Products include Microsoft 365 Apps, Microsoft Office, Microsoft Office Long Term Servicing Channel, Microsoft Outlook.
How do I fix CVE-2025-21357?
No fix has been published for CVE-2025-21357 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2025-21357 being exploited?
There is no known exploitation of CVE-2025-21357 in the wild and no public exploit code.
Other vulnerabilities in Microsoft 365 Apps
- CVE-2024-21413 Microsoft Outlook Improper Input Validation
- CVE-2023-23397 Microsoft Office Outlook Privilege Escalation
- CVE-2024-38189 Microsoft Project Remote Code Execution Vulnerability
- CVE-2023-35311 Microsoft Outlook Security Feature Bypass
- CVE-2026-21514 Microsoft Office Word Reliance on Untrusted Inputs in a Security Decision
Sources
Also known as GHSA-99rf-j72j-fqv4.